When Porsche reached 1M Facebook fans in early 2011, they revealed a custom-made 911 GT3 R Hybrid at the Porsche Museum in Stuttgart.

Earlier this year Porsche reached five million fans on Facebook and asked fans to customize a 911 Carrera 4S, which you can see above.

The unique Porsche 911 Carrera 4S features Aqua Blue Metallic paint scheme, Aerokit Cup with a revised front apron, front spoiler lip, rear spoiler and a fixed wing.

Other highlights include 20-inch white alloy wheels, sport suspension, personalized sill guards with blue illumination and brushed aluminium trim.

Porsche is now giving one of the Facebook fans and a friend of their choice a chance to get behind the wheel of this one-of-a-kind sports car at the Porsche Experience Center in Silverstone.

All you need to do is show how many public Porsche fans you have in your friend-list and the user with the highest number of Porsche Facebook fans in his or her friend-list will win the unique trip to Silverstone.